Biopsy apparatus having integrated thumbwheel mechanism for manual rotation of biopsy cannula

ABSTRACT

A biopsy apparatus includes a housing, a biopsy cannula mounted to the housing, and a cannula rotation mechanism mounted to the housing. The cannula rotation mechanism has a thumbwheel, a first gear, and a second gear. The thumbwheel is configured to rotate about a rotational axis, with the rotational axis being perpendicular to the longitudinal axis of the biopsy cannula. The first gear is mounted in fixed attachment to the thumbwheel. The second gear is mounted in fixed attachment to the biopsy cannula. The first gear is in mesh with the second gear such that the first gear is directly drivably engaged with the second gear to rotate the biopsy cannula about the longitudinal axis when the thumbwheel is rotated.

CROSS REFERENCE TO RELATED APPLICATIONS

None.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a biopsy apparatus, and, moreparticularly, to a biopsy apparatus having an integrated thumbwheelmechanism for manual rotation of a biopsy cannula.

2. Description of the Related Art

A biopsy may be performed on a patient to help in determining whetherthe cells in a biopsied region are cancerous. One biopsy technique usedto evaluate breast tissue, for example, involves inserting a biopsyprobe into the breast tissue region of interest to capture one or moretissue samples from the region. Such a biopsy technique often utilizes avacuum to pull the tissue to be sampled into a sample notch of thebiopsy probe, after which the tissue is severed and collected. One typeof vacuum assisted biopsy apparatus includes a hand-held driver assemblyhaving a vacuum source, and a disposable biopsy probe assemblyconfigured for releasable attachment to the driver assembly. The biopsyprobe typically includes a biopsy cannula, e.g., a needle, having a sideport for receiving the tissue to be sampled.

During a biopsy procedure, it may be desirable to position the side portto various angular positions around a longitudinal axis of the biopsycannula without having to rotate the hand-held driver assembly. Oneconsole-type biopsy device includes a control console tethered to ahand-held driver assembly, wherein the control module is programmed toprovide automatic indexing of the side port to predetermined angularpositions. However, such automatic indexing may limit the ability of thephysician to make real-time changes and/or minute changes to the angularposition of the side port.

Also, it is known to provide manual indexing of the side port of thebiopsy cannula by attaching a knob to the distal end of the biopsycannula, and then simply rotate the knob to position the side port tothe desired angular position. One disadvantage, however, is that such anarrangement requires the physician to hold the handle of the hand-helddriver assembly in one hand, while rotating the knob with the otherhand.

SUMMARY OF THE INVENTION

The present invention provides a biopsy apparatus having a mechanismthat enables a user to operate the biopsy apparatus and manually rotatea side port of a biopsy cannula to a desired rotational position aboutthe longitudinal axis relative to the driver assembly through asingle-handed operation of the biopsy apparatus. Mechanisms may alsoprovide at least one of tactile, aural and visual feedback of therotation of the biopsy cannula, as well as facilitate the selectivelocking of the biopsy cannula from further rotation so as to maintain acurrent rotational position of the side port of the biopsy cannuladuring the harvesting of a tissue sample.

As used herein, the terms “first” and “second” preceding an elementname, e.g., first gear, second gear, etc., are for identificationpurposes to distinguish between different elements having similarcharacteristic, and are not intended to necessarily imply order, unlessotherwise specified, nor are the terms “first” and “second” intended topreclude the inclusion of additional similar elements.

The invention in one form is directed to a biopsy apparatus. The biopsyapparatus includes a driver assembly having a housing configured to begrasped by a user. A biopsy probe mechanism is drivably coupled to thedriver assembly. The biopsy probe mechanism includes a biopsy cannulahaving a cylindrical side wall, a proximal end, a distal end and alongitudinal axis extending between the proximal end and the distal end.The cylindrical side wall defines a lumen and has a side port locatednear the distal end that extends through the side wall to the lumen. Athumbwheel mechanism includes a thumbwheel mounted to the driverassembly to rotate about a first rotational axis, the first rotationalaxis being substantially perpendicular to the longitudinal axis, whereinat least a portion of the thumbwheel is exposed external to the housing.A first gear is mounted to the thumbwheel for coaxial rotation with thethumbwheel about the first rotational axis. A second gear is mounted tothe biopsy cannula for coaxial rotation with the biopsy cannula aboutthe longitudinal axis, the second gear being located to be drivablyengaged by the first gear. A user grasps the housing and rotates thethumbwheel with a single hand to rotatably position the side port of thebiopsy cannula at a desired rotational position about the longitudinalaxis relative to the driver assembly.

The invention in another form is directed to a biopsy apparatus. Thebiopsy apparatus includes a driver assembly having a housing configuredto be grasped by a user. A disposable biopsy probe mechanism isconfigured for releasable attachment to the driver assembly. Thedisposable biopsy probe mechanism is positioned at least partiallywithin the housing when the disposable biopsy probe mechanism isattached to the driver assembly. The disposable biopsy probe mechanismincludes a biopsy cannula having a cylindrical side wall, a proximalend, a distal end and a longitudinal axis extending between the proximalend and the distal end. The cylindrical side wall defines a lumen andhas a side port located near the distal end that extends through theside wall to the lumen. The driver assembly includes a thumbwheel and afirst gear, the thumbwheel and the first gear being coupled for unitarycoaxial rotation about a first rotational axis. The first rotationalaxis is substantially perpendicular to the longitudinal axis. At least aportion of the thumbwheel is exposed external to the housing. The biopsycannula includes a second gear configured for unitary coaxial rotationwith the biopsy cannula about the longitudinal axis. The second gear ispositioned to be drivably engaged by the first gear when the biopsyprobe mechanism is attached to the driver assembly. A user rotates thethumbwheel while grasping the housing to effect a manual rotation of thebiopsy cannula to position the side port of the biopsy cannula at adesired rotational position about the longitudinal axis relative to thedriver assembly.

The invention in another form thereof is directed to a biopsy apparatus.The biopsy apparatus includes a driver assembly having a housingconfigured to be grasped by a user. A biopsy probe mechanism is drivablycoupled to the driver assembly. The biopsy probe mechanism includes abiopsy cannula having a cylindrical side wall, a proximal end, a distalend and a longitudinal axis extending between the proximal end and thedistal end. The cylindrical side wall defines a lumen and having a sideport located near the distal end that extends through the side wall tothe lumen. A thumbwheel mechanism is interposed between the driverassembly and the biopsy probe mechanism. The thumbwheel mechanismincludes a thumbwheel drivably coupled to the biopsy cannula torotatably position the side port of the biopsy cannula at a desiredrotational position about the longitudinal axis relative to the driverassembly. A detent wheel is mounted to the biopsy cannula for coaxialrotation with the biopsy cannula about the longitudinal axis. The detentwheel has a circumferential surface and a plurality of detent recessesformed through the circumferential surface that extends radially towardthe longitudinal axis. The plurality of detent recesses are positionedabout the longitudinal axis at predetermined angular positions. Anengagement device has an engagement element biased in constantengagement with the detent wheel, wherein as the biopsy cannula isrotated the engagement element rides along the circumferential surfaceof the detent wheel and produces at least one of a tactile and an auralfeedback each time the engagement element engages one of the pluralityof detent recesses.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and advantages of this invention,and the manner of attaining them, will become more apparent and theinvention will be better understood by reference to the followingdescription of an embodiment of the invention taken in conjunction withthe accompanying drawings, wherein:

FIG. 1 is a side view of a biopsy apparatus configured in accordancewith an embodiment of the present invention, with a biopsy probemechanism mounted to a driver assembly, and with a side portion brokenaway to expose internal components which are schematically representedin part;

FIG. 2 is a section view of a biopsy cannula of the biopsy apparatus ofFIG. 1, taken along line 2-2 of FIG. 1;

FIG. 3 is a perspective view of the thumbwheel mechanism of the biopsyapparatus of FIG. 1, which includes positioning and locking mechanisms;

FIG. 4 is rear view of the thumbwheel mechanism of FIG. 3;

FIG. 5 is a section view of the biopsy cannula coupled to the detentwheel of the positioning mechanism of FIG. 3, taken along line 5-5 ofFIG. 3;

FIG. 6A is a side view of a portion of the locking mechanism of FIGS. 3and 4 with the locking pin in the unlocked rotational position; and

FIG. 6B is a side view of a portion of the locking mechanism of FIGS. 3and 4 with the locking pin in the locking rotational position.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate an embodiment of the invention, and such exemplifications arenot to be construed as limiting the scope of the invention in anymanner.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, and more particularly to FIG. 1, there isshown a biopsy apparatus 10 which generally includes a driver assembly12 and a biopsy probe mechanism 14.

Driver assembly 12 is configured to provide operative control overbiopsy probe mechanism 14. Driver assembly 12 may be, for example, anon-disposable device, or alternatively a disposable device. As usedherein, the term “non-disposable” is used to refer to a device that isintended for use on multiple patients during the lifetime of the device.Also, as used herein, the term “disposable” is used to refer to a devicethat is intended to be disposed of after use on a single patient.

Accordingly, in some embodiments driver assembly 12 and biopsy probemechanism 14 may be releasably attached to one another. In otherembodiments, however, it is contemplated that driver assembly 12 andbiopsy probe mechanism 14 may be permanently attached to each other toform an integral biopsy apparatus, such that the entire biopsy apparatusis made to be disposable.

Driver assembly 12 includes a housing 16 configured, e.g., ergonomicallydesigned, to be grasped by a user, e.g., a physician. Housing 16 definesa compartment 18 into which biopsy probe mechanism 14 is at leastpartially positioned when biopsy probe mechanism 14 is attached todriver assembly 12, with biopsy probe mechanism 14 being drivablycoupled to driver assembly 12.

Biopsy probe mechanism 14 is generally intended to be disposable as aunit. In the present embodiment, biopsy probe mechanism 14 is configuredfor releasable attachment to driver assembly 12. As used herein, theterm “releasable attachment” means a configuration that facilitates anintended temporary connection followed by selective detachment involvinga manipulation of disposable biopsy probe mechanism 14 relative todriver assembly 12, e.g., without the need for tools. Biopsy probemechanism 14 includes a frame 19 to which a biopsy cannula 20 and acutting cannula 22 are mounted. Biopsy cannula 20 and a cutting cannula22 are arranged coaxially with respect to a longitudinal axis 24.

Cutting cannula 22 has a distal cutting end 26.

Referring to FIGS. 1 and 2, biopsy cannula 20 has a cylindrical sidewall 28 having a proximal end 30 and a distal end 32, wherein thelongitudinal axis 24 extends between the proximal end 30 and the distalend 32. Cylindrical side wall 28 defines a lumen 34 and has a side port36 located near distal end 32. Side port 36 extends through the sidewall to the lumen 34 to a portion of the lumen 34 referred to as thesample chamber, or basket, 38. Biopsy cannula 20 may, for example, be inthe form of a hollow needle having a piercing tip 40.

Driver assembly 12 further includes a user interface 42 located to beexternally accessible to the user with respect to housing 16 forreceiving operation commands from the user, e.g., through one or morepushbuttons, and may also include a display, e.g., one or more lights oran LCD (liquid crystal display), to display information to the user. Acontroller 44 is communicatively coupled user interface 42. Controller44 may include, for example, a microprocessor and associated memory (notshown) for executing program instructions to perform functionsassociated with the harvesting of biopsy tissue samples during a biopsyprocedure.

There is contained within housing 16 an electromechanical drive 46 and avacuum source 48. Electromechanical drive 46 is connected in electricalcommunication with controller 44. Electromechanical drive 46 is furtherdrivably coupled (illustrated by dashed lines) to the biopsy probemechanism 14 and to the vacuum source 48 to selectively and operativelycontrol vacuum source 48 and/or cutting cannula 22. Electromechanicaldrive 46 may include, for example, one or more of a linear drive thatconverts rotational motion to linear motion (e.g., a worm geararrangement, rack and pinion arrangement, solenoid-slide arrangement,etc.) and a rotational drive that may include one or more of a gear,gear train, belt/pulley arrangement, etc., for effecting operation ofcutting cannula 22 of biopsy probe mechanism 14 and/or vacuum source 48.

Vacuum source 48 may be, for example, a peristaltic pump, a diaphragmpump, syringe-type pump, etc. Vacuum source 48 may be permanentlyintegrated into driver assembly 12, or alternatively may be permanentlyintegrated as a part of the biopsy probe mechanism 14. In either case,vacuum source 48 is coupled in fluid communication with lumen 34 ofbiopsy cannula 20.

During a biopsy procedure, for example, biopsy cannula 20 and cuttingcannula 22 are relatively positioned such that side port 36 is closed bycutting cannula 22. Biopsy cannula 20 and cutting cannula 22 areadvanced into the tissue region to be sampled of a patient. Commands aresent via user interface 42 to electromechanical drive 46 to open sideport 36 by retracting cutting cannula 22 along longitudinal axis 24, andto operate vacuum source 48 so as to selectively draw tissue though sideport 36 of biopsy cannula 20 into sample chamber 38. Once tissue isreceived through side port 36, electromechanical drive 46 is controlledto cause cutting cannula 22 to advance linearly along longitudinal axis24 to close side port 36 and sever the tissue prolapsed into samplechamber 38. In some circumstances, it may be desirable forelectromechanical drive 46 to cause cutting cannula 22 to rotate oroscillate during the linear advancement. The severed tissue may then beadvanced to a tissue collection receptacle 49, such as for example byvacuum, where the tissue samples may be retrieved. Alternatively, in anembodiment wherein vacuum source 48 is in direct fluid communicationwith lumen 34 (i.e., to the exclusion of tissue collection receptacle49), each of the tissue samples may simply be retained in lumen 34 ofbiopsy cannula 20.

Referring also to FIGS. 3-5, further convenience may be provided to theuser by the inclusion of a thumbwheel mechanism 50 interposed betweendriver assembly 12 and biopsy probe mechanism 14 to facilitate a manualrotation of biopsy cannula 20 relative to driver assembly 12. Therotation of biopsy cannula 20 may be in either the clockwise orcounterclockwise directions, as indicated by double-headed arrow 51.More particularly, a user may grasp housing 16 of driver assembly 12with a single hand and may operate thumbwheel mechanism 50 with a thumbor finger of the same hand to rotatably position side port 36 of biopsycannula 20 at a desired rotational position, e.g. rotational position52, about longitudinal axis 24 relative to driver assembly 12, whereinthe desired rotational position 52 is an angular value, e.g., 30 degreesin the present example, in a range of angular values from 0 degrees to360 degrees, inclusive, as illustrated in FIG. 5.

As best shown in FIGS. 3 and 4, thumbwheel mechanism 50 includes athumbwheel 54, a first gear 56 and a second gear 58. Each of first gear56 and second gear 58 may be, for example, a bevel gear.

Thumbwheel 54 and first gear 56 is rotatably mounted to driver assembly12 by an axle/bearings arrangement 60, including bearings 60-1, 60-2 andaxle 60-3, to rotate about a first rotational axis 62. The unit formedby thumbwheel 54, first gear 56 and axle/bearing arrangement 60 may bemounted to housing 16 of driver assembly 12 via a mounting plate 61 anda pair of screws 63. First rotational axis 62 is positioned to besubstantially perpendicular to longitudinal axis 24. As shown in FIGS. 1and 4, at least a portion 55 of thumbwheel 54 is exposed external tohousing 16 of driver assembly 12.

First gear 56 is coupled, e.g., mounted in fixed attachment, tothumbwheel 54 for unitary coaxial rotation with thumbwheel 54 aboutfirst rotational axis 62. Second gear 58 is coupled, e.g., mounted infixed attachment, to biopsy cannula 20 for unitary coaxial rotation withbiopsy cannula 20 about longitudinal axis 24. As shown, second gear 58,and in turn biopsy probe mechanism 14, is located to be drivably engagedby first gear 56 when said biopsy probe mechanism 14 is attached todriver assembly 12.

Accordingly, the user grasps housing 16 and rotates thumbwheel 54 with asingle hand to effect a manual rotation of biopsy cannula 20 to therebyrotatably position side port 36 of biopsy cannula 20 at a desiredrotational position, e.g., rotational position 52, about longitudinalaxis 24 relative to driver assembly 12 in a range of 0 degrees through360 degree, as illustrated in FIG. 5. Thumbwheel 54 may include anindicia, e.g., “UP”, located on the periphery of thumbwheel 54 tocoincide with the designated “up” position, i.e., the 0/360 degreeposition of side port 36 (see FIG. 5). As also shown in FIG. 3, otherindicia, such as “LT” for left and “RT” for right, may be included toaid in indicating the rotational direction of biopsy cannula 20.

Thumbwheel mechanism 50 may further include a positioning mechanism 64coupled to said biopsy cannula 20 to provide resistive positioning ofside port 36 of biopsy cannula 20 at discrete angular positions aboutlongitudinal axis 24, and may further provide at least one of tactileand aural feedback to the user as biopsy cannula 20 is rotated aboutlongitudinal axis 24 relative to driver assembly 12.

Referring to FIGS. 3-5, positioning mechanism 64 includes a detent wheel66, an engagement device 68, and a lock mechanism 70. While the presentembodiment includes both engagement device 68 and lock mechanism 70, itis contemplated that alternatively it may be desirable to have only oneof engagement device 68 and lock mechanism 70 without the other. In suchan alternative, one of engagement device 68 and lock mechanism 70 wouldsimply be deleted from the design.

Detent wheel 66 is mounted to biopsy cannula 20 for unitary coaxialrotation with biopsy cannula 20 about longitudinal axis 24. Detent wheel66 has a circumferential surface 72 and a plurality of detent recesses74-1, 74-1 . . . 74-N formed through circumferential surface 72 andextending radially toward longitudinal axis 24, wherein “N” is the totalnumber of detents and is a positive integer. Each of the plurality ofdetent recesses 74-1 through 74-N may be formed, for example, as acup-shaped void having a tapered side wall that is curved or afrustoconical.

The plurality of detent recesses 74-1 through 74-N are positioned aboutlongitudinal axis 24 at predetermined angular positions, as illustratedin FIG. 5. In the present exemplary embodiment, the plurality of detentrecesses 74-1 through 74-N are arranged in uniform angular increments of30 degrees, and thus the number of detents is N=12. However, for morecoarse angular increments N may be less than 12 and for finer (moreminute) angular increments N may be greater than 12, as desired.

Engagement device 68 is mounted to biopsy probe mechanism 14, such as toframe 19. Engagement device 68 includes an engagement element 76 biasedby a spring 78 to be in constant engagement with detent wheel 66.Engagement element 76 may be, for example a metallic ball or plug havinga rounded or tapered end. Spring 78 may be, for example a coil spring,leaf spring, etc. Thus, as biopsy cannula 20 is rotated, engagementelement 76 rides along circumferential surface 72 of detent wheel 66 andproduces a resistive positioning of biopsy cannula 20, which isexperienced by the user as a tactile interruption and/or aural feedback(e.g., a click sound) each time engagement element 76 engages one of theplurality of detent recesses 74-1 through 74-N of detent wheel 66.

Also, in some biopsy applications as illustrated in FIG. 5, theplurality of detent recesses 74-1 through 74-N may be positioned aboutlongitudinal axis 24 at uniform angular increments and be of asufficient population N such that an opening defined by side port 36 ata current position (e.g., 74-1) will overlap with the opening of sideport 36 at a next position (e.g., 74-2) at each of the angularincrements, whereby providing a full 360 degrees of sampling capability.

In general, lock mechanism 70 includes a locking pin 80 having aproximal end 82 and an engagement end 84, and is longitudinally arrangedalong a locking axis 86. A head portion 88 is attached, or formedintegral with, the proximal end 82 of locking pin 80. A shaft portion 90extends from head portion 88 toward engagement end 84. A spring 91biases locking pin 80 along locking axis 86 toward detent wheel 66.

Thus, locking pin 80 is configured for linear movement along lockingaxis 86 relative to circumferential surface 72 of detent wheel 66 forselective locking engagement of engagement end 84 with one of theplurality of detent recesses 74-1 through 74-N of detent wheel 66 toprevent a rotation of biopsy cannula 20 from a current angular positionof side port 36 of biopsy cannula 20 relative to driver assembly 12.

Referring also to FIGS. 6A and 6B, engagement end 84 of locking pin 80may have a tapered portion 92 and a non-tapered portion 94 angularlyoffset, e.g., at 90 degrees, from tapered portion 92 about locking axis86. In the present embodiment, tapered portion 92 may have a curved orbeveled faces 95 that smoothly transitions to the tip end 96 ofengagement end 84, and the non-tapered portion 94 may have a straightfaces 97 that abruptly transition, e.g., at 90 degrees, to the tip end96 of engagement end 84.

In operation, for example, when locking pin 80 is positioned in anunlocked rotational position 98 relative to locking axis 86 and detentwheel 66, as illustrated in FIG. 6A, engagement end 84 rides alongcircumferential surface 72 of detent wheel 66 and tapered portion 92sequentially passes into and out of a respective detent recess of theplurality of detent recesses 74-1 through 74-N of detent wheel 66 (seealso FIGS. 3-5) as biopsy cannula 20 is rotated, thereby operatingsimilarly to engagement device 68 in providing a positioning mechanismthat provides at least one of aural, visual and tactile feedback of aprogressive rotation of biopsy cannula 20.

However, when locking pin 80 is positioned in a locking rotationalposition 100 relative to locking axis 86 and detent wheel 66, asillustrated in FIG. 6B, as biopsy cannula 20 is rotated engagement end84 rides along circumferential surface 72 of detent wheel 66 andnon-tapered portion 94 lockably engages a next encountered detent recessof the plurality of detent recesses 74-1 through 74-N of detent wheel 66(see also FIGS. 3-5) to lock biopsy cannula 20 from further rotation.Locking pin 80 is released from locking rotational position 100 by afurther 90 degree rotation of locking pin 80 relative to locking axis86, in either rotational direction, to unlocked rotational position 98.

While this invention has been described with respect to at least oneembodiment, the present invention can be further modified within thespirit and scope of this disclosure. This application is thereforeintended to cover any variations, uses, or adaptations of the inventionusing its general principles. Further, this application is intended tocover such departures from the present disclosure as come within knownor customary practice in the art to which this invention pertains andwhich fall within the limits of the appended claims.

1-16. (canceled)
 17. A biopsy apparatus, comprising: a housing; a biopsycannula mounted to the housing, the biopsy cannula having a side wall, aproximal end, a distal end, and a longitudinal axis extending betweenthe proximal end and the distal end, the side wall defining a lumen andhaving a side port proximal to the distal end that extends through theside wall to the lumen; and a cannula rotation mechanism mounted to thehousing, the cannula rotation mechanism having a thumbwheel, a firstgear, and a second gear, the thumbwheel configured to rotate about arotational axis, the rotational axis being perpendicular to thelongitudinal axis of the biopsy cannula, the first gear mounted in fixedattachment to the thumbwheel, the second gear mounted in fixedattachment to the biopsy cannula, and the first gear being in mesh withthe second gear such that the first gear is directly drivably engagedwith the second gear to rotate the biopsy cannula about the longitudinalaxis when the thumbwheel is rotated.
 18. The biopsy apparatus of claim17, further comprising a feedback device configured to provide at leastone of tactile and aural feedback as the biopsy cannula is rotatedrelative to the housing.
 19. The biopsy apparatus of claim 17, furthercomprising: a detent wheel mounted in fixed attachment to the biopsycannula, the detent wheel having a plurality of detent recessespositioned about the longitudinal axis at predetermined angularpositions; and an engagement element biased in constant engagement withthe detent wheel to sequentially engage each of the plurality of detentrecesses to produce at least one of tactile and aural feedback each timethe engagement element engages one of the plurality of detent recesses.20. The biopsy apparatus of claim 17, further comprising: a detent wheelmounted in fixed attachment to the biopsy cannula, the detent wheelhaving a plurality of detent recesses positioned about the longitudinalaxis at predetermined angular positions; and a lock mechanism mounted tothe housing, the lock mechanism including a locking pin biased along alocking axis in constant engagement with the detent wheel, the lockingpin including an engagement end having a tapered portion and anon-tapered portion angularly offset from the tapered portion about thelocking axis, the locking pin having a first position and a secondposition, wherein: in the first position the tapered portionsequentially passes into and out of a respective detent recess of theplurality of detent recesses of the detent wheel as the biopsy cannulais rotated thereby providing at least one of aural, visual and tactilefeedback of a progressive rotation of the biopsy cannula, and in thesecond position the engagement end rides against the detent wheel andthe non-tapered portion lockably engages a next detent recess of theplurality of detent recesses of the detent wheel as the biopsy cannulais rotated to lock the biopsy cannula from further rotation.
 21. Thebiopsy apparatus of claim 17, wherein the biopsy cannula and the cannularotation mechanism are configured as a disposable biopsy probe, thedisposable biopsy probe configured for releasable attachment to thehousing.
 22. The biopsy apparatus of claim 17, configured such that auser rotates the thumbwheel while grasping the housing to effect amanual rotation of the biopsy cannula to position the side port of thebiopsy cannula at a desired rotational position about the longitudinalaxis.
 23. The biopsy apparatus of claim 17, further comprising: a detentwheel mounted in fixed attachment to the biopsy cannula for coaxialrotation with the biopsy cannula about the longitudinal axis, the detentwheel having a circumferential surface and a plurality of detentrecesses formed through the circumferential surface and extendingradially toward the longitudinal axis, the plurality of detent recessesbeing positioned about the longitudinal axis at predetermined angularpositions; and a lock mechanism having a locking pin biased along alocking axis in constant engagement with the detent wheel, the lockingpin including an engagement end having a tapered portion and anon-tapered portion angularly offset from the tapered portion about thelocking axis, the locking pin having a first rotational positionrelative to the locking axis wherein the engagement end rides along thecircumferential surface of the detent wheel and the tapered portionsequentially passes into and out of a respective detent recess of theplurality of detent recesses of the detent wheel as the biopsy cannulais rotated thereby providing at least one of aural, visual and tactilefeedback of a progressive rotation of the biopsy cannula, and thelocking pin having a second rotational position relative to the lockingaxis wherein the engagement end rides along the circumferential surfaceof the detent wheel and the non-tapered portion lockably engages a nextdetent recess of the plurality of detent recesses of the detent wheel asthe biopsy cannula is rotated to lock the biopsy cannula from furtherrotation.
 24. A biopsy apparatus, comprising: a driver assembly having ahousing configured to be grasped by a user; a biopsy probe drivablycoupled to the driver assembly, the biopsy probe including a biopsycannula having a cylindrical side wall, a proximal end, a distal end anda longitudinal axis extending between the proximal end and the distalend, the cylindrical side wall defining a lumen and having a side portlocated near the distal end that extends through the side wall to thelumen; and a cannula rotation mechanism mounted to the housing, thecannula rotation mechanism having a thumbwheel, a first gear, and asecond gear, the thumbwheel configured to rotate about a rotationalaxis, the rotational axis being perpendicular to the longitudinal axisof the biopsy cannula, the first gear mounted in fixed attachment to thethumbwheel, the second gear mounted in fixed attachment to the biopsycannula, and the first gear being in mesh with the second gear such thatthe first gear is directly drivably engaged with the second gear torotate the biopsy cannula about the longitudinal axis when thethumbwheel is rotated.
 25. The biopsy apparatus of claim 24, furthercomprising a feedback device configured to provide at least one oftactile and aural feedback as the biopsy cannula is rotated relative tothe housing.
 26. The biopsy apparatus of claim 24, further comprising: adetent wheel mounted in fixed attachment to the biopsy cannula, thedetent wheel having a plurality of detent recesses positioned about thelongitudinal axis at predetermined angular positions; and an engagementelement biased in constant engagement with the detent wheel tosequentially engage each of the plurality of detent recesses to produceat least one of tactile and aural feedback each time the engagementelement engages one of the plurality of detent recesses.
 27. The biopsyapparatus of claim 24, further comprising: an engagement element biasedin constant engagement with the detent wheel to sequentially engage eachof the plurality of detent recesses to produce at least one of tactileand aural feedback each time the engagement element engages one of theplurality of detent recesses; and a lock mechanism mounted to thehousing, the lock mechanism including a locking pin biased along alocking axis in constant engagement with the detent wheel, the lockingpin including an engagement end having a tapered portion and anon-tapered portion angularly offset from the tapered portion about thelocking axis, the locking pin having a first position and a secondposition, wherein: in the first position the tapered portionsequentially passes into and out of a respective detent recess of theplurality of detent recesses of the detent wheel as the biopsy cannulais rotated thereby providing at least one of aural, visual and tactilefeedback of a progressive rotation of the biopsy cannula, and in thesecond position the engagement end rides along the detent wheel and thenon-tapered portion lockably engages a next detent recess of theplurality of detent recesses of the detent wheel as the biopsy cannulais rotated to lock the biopsy cannula from further rotation.
 28. Thebiopsy apparatus of claim 24, wherein the biopsy probe is configured forreleasable attachment to the housing.
 29. The biopsy apparatus of claim24, configured such that a user rotates the thumbwheel while graspingthe housing to effect a manual rotation of the biopsy cannula toposition the side port of the biopsy cannula at a desired rotationalposition about the longitudinal axis.
 30. The biopsy apparatus of claim24, further comprising: a detent wheel mounted in fixed attachment tothe biopsy cannula for coaxial rotation with the biopsy cannula aboutthe longitudinal axis, the detent wheel having a circumferential surfaceand a plurality of detent recesses formed through the circumferentialsurface and extending radially toward the longitudinal axis, theplurality of detent recesses being positioned about the longitudinalaxis at predetermined angular positions; and a lock mechanism having alocking pin biased along a locking axis in constant engagement with thedetent wheel, the locking pin including an engagement end having atapered portion and a non-tapered portion angularly offset from thetapered portion about the locking axis, the locking pin having a firstrotational position relative to the locking axis wherein the engagementend rides along the circumferential surface of the detent wheel and thetapered portion sequentially passes into and out of a respective detentrecess of the plurality of detent recesses of the detent wheel as thebiopsy cannula is rotated thereby providing at least one of aural,visual and tactile feedback of a progressive rotation of the biopsycannula, and the locking pin having a second rotational positionrelative to the locking axis wherein the engagement end rides along thecircumferential surface of the detent wheel and the non-tapered portionlockably engages a next detent recess of the plurality of detentrecesses of the detent wheel as the biopsy cannula is rotated to lockthe biopsy cannula from further rotation.